The first generation of models for multi-hop question answering utilizes a one-step reader [1]}, [2]}, [3]}, [4]}, [5]} to capture the interaction between the question and relevant contexts for the prediction of the answer as well as the supporting sentences. In order to model the explainable multi-step reasoning process, researchers explore to decompose the multi-hop question into easier single-hop questions and solve sub-questions to reach the answer [6]}, [7]}.
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